The invention relates to a method for producing assembled synthetic resin structures with hollow chambers.
The invention furthermore relates to an assembled structure with a hollow chamber.
Such a method, and the corresponding hollow chamber structure, are disclosed in GB 22 26 711. If it is desired to use such a hollow structure in areas in which the structure is to be gas-tight with respect to the environment, it is disadvantageous that such a structure tends to be leaky. To seal such a hollow structure after manufacture, for example with additional elastomer seals, is, however, expensive and the hollow structure would therefore be more expensive. Furthermore, the insertion of floors into containers by friction welding is disclosed in Swarz, O., Kunststoffverarbeitung (Plastic Processing), Wurzburg, page 201.
It is therefore the object of the invention to improve an apparatus of the kind described above so as to create a flexible, safe and inexpensive manufacturing method and a device which is gas-tight, reliable and inexpensive.
This object is achieved in accordance with the invention in that the method for the production of assembled synthetic resin hollow structures from at least two synthetic resin housing parts with matching sealing and wall surfaces for producing an oscillation tube cross section comprises the following steps: providing a first synthetic resin housing part with a first sealing surface and at least a first half wall, providing a second synthetic resin housing part with a second sealing surface and at least one second half wall, disposing the first synthetic resin housing part in a first tool which supports the first synthetic resin housing part in the vicinity of the first sealing surface, disposing the second synthetic resin housing part in a second tool which supports the second synthetic resin housing part in the vicinity of the second sealing surface, arranging the parts with the matching sealing surfaces so that the corresponding sealing surfaces as well as the at least one first half wall of the first synthetic resin housing part and the at least one second half wall of the second synthetic resin housing part come in contact with one another, applying a binding force to all of the sealing surfaces, wherein at least one of the tools is moved relative to the other tool in order thus to produce a friction force to bond together the individual parts. The synthetic resin housing parts are thus bonded by friction or vibration welding. An alternative method for making assembled synthetic resin hollow structures from at least two synthetic resin housing parts with matching sealing surfaces and wall surfaces for producing stable hollow structures comprises the following steps: providing a first synthetic resin housing part with a first sealing surface and at least a first half wall, providing a second synthetic resin housing part with a second sealing surface and at least one second half wall, disposing the first synthetic resin housing part in a first tool which supports the first synthetic resin housing part in the vicinity of the first sealing surface, disposing the second synthetic resin housing part in a second tool which supports the second synthetic resin housing part in the vicinity of the second sealing surface, arranging the parts with the matching sealing surfaces so that the corresponding sealing surfaces as well as the at least one first half wall of the first synthetic resin housing part and the at least one second half wall of the second synthetic resin housing part come in contact with one another, application of bonding force to the entire sealing surfaces, wherein at least one of the tools is moved relative to the other tool in order thus to produce a frictional force to join the individual parts. Thus an assembled hollow structure is formed, which comprises at least two housing parts with matching sealing surfaces and at least one half wall per synthetic resin housing part, wherein the wall halves mate with one another so as to strengthen the hollow structure, and wherein the matching sealing surfaces and the wall halves are bonded by means of the friction force.
An alternative assembled hollow structure is likewise provided, having an inlet and an outlet, which comprises at least two housing parts with matching sealing surfaces and at least one half wall for each synthetic resin housing part, wherein the wall halves match to produce a oscillation tube cross section inside the housing, and the matching sealing surfaces and the wall halves are joined together by friction force and the inlet communicates with the outlet through the oscillation tube cross section.
In a special variant, an air intake filter for an internal combustion engine is formed, with noise damping in front of and/or in back of a filter, wherein a previously described assembled hollow structure is used.
An advantageous embodiment of the invention provides that, in one of the previously described methods, the bonding force is applied by high pressure and/or high frequencies, especially in the ultrasonic range.
In another advantageous embodiment it is provided that the wall halves are arranged substantially transversely to the direction of the welding vibration. On the one hand this makes the hollow structure more stable, and on the other hand it is possible by this measure to produce labyrinth-like chambers having, for example, a sound-damping action.
Also, it can be arranged according to the invention for at least one half wall to have at least one cross rib, which is advantageous especially when a transverse half wall is joined to its matching other half by means of vibration welding as so-called remote welding. The cross rib prevents excessive deflection of the wall halves during vibration welding, which would make welding impossible.
An advantageous embodiment of the invention provides that the half wall of a synthetic resin housing part is a dome-like bulge of the synthetic resin housing wall which extends into the housing interior. This three-dimensional configuration of the housing wall also increases the strength, so that the wall in the area to be welded will not impair the quality of the weld, much less render it impossible, due to excessive deflection.
Advantageous further embodiments are described hereinafter.
These and additional features of preferred embodiments of the invention will be found not only in the claims but also in the description and the drawings, and the individual features can each be realized by itself or together in the form of subcombinations in embodiments of the invention and in other fields, and can constitute advantageous as well as independently patentable embodiments, for which protection is hereby claimed.